1. Field of the Invention
The present invention relates to an automated device for releasing items within a confined space. In particular, the present invention relates to an automated pickup head which is used to grip egg cartons or trays and place those egg cartons or trays in stacks in a shipping container or basket.
2. Description of the Prior Art
Several prior art devices are designed to allow the gripping or release of items within a confined space or insertion of egg cartons within a confined shipping container.
U.S. Pat. No. 4,765,487 to George N. Bliss assigned to Diamond Automations, Inc. shows an apparatus which includes a device for inserting a stack of egg cartons within a shipping container. In that patent, a plastic strip is wrapped around a stack of egg cartons and used to insert the stack into the shipping container. Thereafter, the plastic slip is withdrawn from the shipping container by releasing one end of the strip and pulling the other end around the stack and out of the shipping container.
U.S. Pat. No. 4,648,646 assigned to Mollers Maschinenfabrik GmbH shows a device for releasing items such as cement bags in a confined space between similar bags. In the device of that invention, gripping arms are mounted on rollers which roll within guide rails on the device.
U.S. Pat. No. 5,338,150, assigned to Focke & Co. shows a device for palletizing cartons. The device includes carrying arms with carrying legs which pivot from a vertical to a horizontal position under the action of short stroke cylinders, while the gripping arms are moved by another set of cylinders.
U.S. Pat. No. 5,463,847, assigned to FPS Food Processing Systems, Inc. describes an automated device designed to grip egg cartons and insert those egg cartons into a shipping container having a minimum of spacing between the inside walls of the shipping container and the egg cartons. The device of that patent uses two retractable "wings" on the pickup head, in conjunction with two curved arms which move along guide wheels. Operation of the apparatus of U.S. Pat. No. 5,463,847 requires the control and use of four hydraulic cylinders.